All that matters is the load on the rear drive wheels. I have had a camper load of as much as 3700 lbs. with a Porta-bote, 6hp outboard, etc. and only 100 lbs. was carried by the front wheels when comparing the CAT scale weights with and without the camper and its load for travel.
Not surprised about the airbags bracket breaking. Trucks with campers are not a good use for airbags. Adding leaf springs, either custom, factory, or Supersprings works much better with nothing to break and the suspension works like the factory suspension so the shocks do a better job of dampening motion and the ride is better rather than worse.